1. Field of the Invention
The invention relates to a junction box, especially for a PV (photovoltaic) junction box for connecting to a solar panel.
2. Description of Related Art
Junction boxes are used in a wide variety of technical sectors in order to make electrical connections between electric lines and an electrical device. Solar panels have a large number of solar cells which are used to convert power from sunlight. The power generated by the solar cells is conveyed via electric lines, for example to a rectifier, for feeding into an alternating current (AC) network or to a battery. A PV junction box is generally provided for electrical connection to the lines of the solar panel.
A conventional junction box is known from US patent application No. 2009/0084570A1, issued on Apr. 2, 2009. The junction box has a case and terminals mounted to the case, the case define a positive input port and a negative output port, and the terminals have a first dispersing pad disposed near the positive input port and used for positive electrode, a second dispersing pad disposed near the negative output port and used for negative electrode, and a third dispersing pad disposed between the first and the second dispersing pads. All of above dispersing pads have a same area, however, usually a positive electrode occurs much more heats relative to a negative electrode with same area, so the first dispersing pad may accumulate heats within the junction box that may influence a lift of the junction box.
Hence, an improved PV junction box is highly desired to overcome the aforementioned disadvantages of the prior art.